DEN93LA085 · LET L-13
LET L-13 · Accident: loss of control in flight during initial climb
From Val Air Airport (CD82) to Val Air Airport (CD82)
Event
- NTSB case
- DEN93LA085
- Event typeAccident: someone killed or seriously injured, or the aircraft substantially damaged (NTSB definition). Incident: an occurrence that affected or could have affected safety, short of that. Glossary
- Accident
- InvestigationHow far the investigation had got when the record was published: preliminary, ongoing, final or completed. Unknown where the source does not say. Glossary
- Completed
- API-reported fatalities
- 0 · all aircraft and ground
- Ground fatalities
- 0
- OperationWhat kind of flying it was, grouped by the rules it flew under: airline (US Part 121), air taxi and commuter (Part 135), general aviation (Part 91 and similar), military or government. Glossary
- General aviation
- WeatherVisual meteorological conditions (VMC): good enough to fly by looking outside. Instrument conditions (IMC): cloud or low visibility, flying by instruments. Glossary
- Visual Meteorological Cond
LET L-13
- Aircraft type
- Let L-13
- Category
- Glider
- RegistrationThe aircraft's tail number, such as N12345 or G-ABCD. Registrations are reissued, so the same one years apart can be a different aircraft. Glossary
- N48069
- Operator
- ST. Clair, Lavern D.
- Onboard fatalities
- Unknown
- Route
- From Val Air Airport (CD82)To Val Air Airport (CD82)
- Aircraft age
- Not recorded
- Flight rulesThe regulations the flight operated under: in the US, Part 91 (general aviation), Part 121 (airlines), Part 135 (air taxi and commuter) and others; for flights abroad, the NTSB's coarser commercial or non-commercial code. Glossary
- Part 91: General Aviation
- Phase of flightThe stage of the flight when things started to go wrong: standing, taxi, takeoff, initial climb, en route, maneuvering, approach or landing. Glossary
- Initial climb
- First occurrenceThe single coded event the NTSB judges best describes what happened (records from 2008 on). Older records name the first occurrence in the sequence instead. Glossary
- Loss of control in flight
- Also codedOther events the NTSB coded in the sequence, such as a wire strike after a loss of power. Flight Findings uses them for its kinds of event. Glossary
- Stall
- DamageDestroyed: beyond practical repair. Substantial: damage that affects the structure, performance or handling and normally needs major repair. Minor: less than that. Glossary
- Destroyed
Cause areas
- Pilot of other aircraft › Safety advisory, not issued
Approximate · Coordinates as recorded by the NTSB; no uncertainty radius is established.
NTSB narrative
BOTH THE GLIDER AND TOW PLANE PILOTS AGREED THAT IF THE GLIDER WAS AIRBORNE BY MIDFIELD, THE GLIDER PILOT WOULD RELEASE THE TOW. TAKEOFF WAS NORMAL AND THE GLIDER WAS AIRBORNE BEFORE MIDFIELD. THE TOW PLANE PILOT, HOWEVER, ENCOUNTERED A WIND GUST OR SHEAR THAT LIFTED THE TOW PLANE, THEN CAUSED IT TO SETTLE TO THE GROUND. HE SENSED HE WAS NOT ACCELERATING AND GAINING ALTITUDE AS HE SHOULD. HE RELEASED THE TOW LINE. THE GLIDER PILOT FOLLOWED THE TOW PLANE TO MAINTAIN PROPER TOW POSITION. AS THE TOW PLANE CLIMBED OUT, HE REALIZED HE HAD BEEN RELEASED AND SAW HIS AIRSPEED DETERIORATING. THE RIGHT WING BEGAN TO STALL AND DROP. HE ATTEMPTED TO LAND IN AN EMPTY PARKING LOT, BUT THE RIGHT WING STRUCK THE RAILING OF AN OBSERVATION DECK. THE TOW PLANE PILOT SAID HE FAILED TO WARN THE GLIDER PILOT ABOUT THE TOW RELEASE BECAUSE HE ASSUMED HE WOULD SEE AND FEEL THE RELEASE, AND HE DID NOT WANT TO DISTRACT HIM FROM FLYING AND GLIDER.
Probable cause
THE FAILURE OF THE TOW PLANE PILOT TO WARN THE GLIDER PILOT THAT HE WAS RELEASING THE TOW LINE. A FACTOR WAS: AN INADVERTENT STALL BY THE PILOT IN COMMAND.
Verbatim NTSB analysis and probable cause from the NTSB dataset
Sources
NTSB record DEN93LA085
- Event ID
- 20001211X12898
- Case number
- DEN93LA085
- Dataset
- historical-pre2008
- Source SHA-256
- 89e2df6d848e7ab3b42e7d7c7a03ff403303057a26ca04c95b3ea67201c3ce74
Source notes (4)
- Unreviewed is an editorial label, not an investigation status. API-sourced is not report-checked or human-reviewed. Explicit event totals are used without summing aircraft injury tables; onboard allocation is withheld. Unknown values remain unknown. The operation category is mapped from the NTSB-reported FAR part and has not been reviewed.
- Filled from the NTSB case API where the bulk record had no value: investigation status. Values present in the bulk record are kept.
- The date is the local date, which is the same as the UTC date the NTSB stores.
- API snapshot SHA-256: 8c1a975cce91d850d5f8bff63295f17cbee601aca8d7eb022099e662b41af436; retrieved 2026-09-21T22:51:57.647Z.